1. Field of the Invention
The present invention relates to light emitting diodes, and in particular, an organic light emitting diode display.
2. Description of Related Art
The recent trend to thin, lightweight personal computers and televisions sets created demands for thin, lightweight display devices. Currently, flat panel displays are satisfying these demands and are being substituted for conventional cathode ray tubes (CRT).
Exemplary flat panel displays include liquid crystal displays (LCD), field emission displays (FED), organic light emitting diode (OLED) displays, and plasma display panels (PDP). The OLED display appears to be the most promising of the flat panel displays, because of its low power consumption, fast response time, wide viewing angle, and high contrast ratio.
In general, an OLED display is a self-emissive display device, which includes two electrodes and an organic light emitting layer interposed between the two electrodes, with one electrode (anode) injecting holes into the light emitting layer and the other electrode (cathode) injecting electrons. Excitons are formed when the injected electrons and holes recombine, and emit light by discharging energy.
Because the red, green, and blue light emitting materials currently employed in OLEDs display exhibit different emission efficiencies, there is a need to design and produce pixels based on the lowest emission efficiency, in order to control red, green, and blue light emissions in an equivalent manner, and thereby decreasing pixel aperture ratio.